Extruder, conductive foam and preparation method thereof

Abstract

The application discloses an extruder, conductive foam and a preparation method thereof, and belongs to the technical field of conductive foam. Metal sheets are fed to a first feeding channel of the extruder, and mixed materials of conductive silica gel raw materials are fed to a second feeding channel. The metal sheets in the first feeding channel and the mixed materials in the second feeding channel are simultaneously fed to an extrusion outlet by a feeding assembly, and the mixed materials are adhered to the metal sheets by extrusion through the extrusion outlet, so that a double-layer extruded material is obtained. The double-layer extruded material is vulcanized, the mixed materials are adhered to the metal sheets, and the conductive foam is obtained. The conductive foam provided in the examples of the application has a metal layer which is not prone to cracking and falling off, has high welding strength, and has good structural stability.

Description

Technical Field

[0001] This application relates to the field of conductive foam technology, and more specifically, to an extruder, conductive foam, and a method for preparing the same. Background Technology

[0002] SMT conductive foam (hereinafter referred to as SMT conductive foam) is generally made by wrapping an elastomer with a polymer film plated with conductive metal layers such as copper, tin, and gold. The elastomer is usually made of silicone with good resilience. Currently, the research and development and production of SMT conductive foam products involves complex processes, including extrusion, vulcanization, and cooling of the elastomer, as well as bonding the elastomer and conductive layer using a mold. Some inherent problems exist in the production process, such as: 1. During the bonding process between the elastomer and the conductive layer, adhesive may overflow onto the surface of the conductive layer, reducing its electrical performance; 2. When the finished product is wrapped or cut, the surface of the conductive layer may appear uneven; 3. The conductive layer may break during molding.

[0003] Furthermore, in actual use, existing SMT conductive foam, after being soldered onto the PCB, is prone to being lifted by external forces under long-term, repeated compressive loads, thus separating from the PCB and losing its conductivity. Additionally, under repeated, concentrated pressure, the metal layer on the surface of the SMT conductive foam may crack or peel off, further affecting performance. These problems pose significant challenges to the production and use of SMT conductive foam, and the multiple processes involved make it difficult to improve yield rates, thus creating difficulties for large-scale production. Summary of the Invention

[0004] Based on the above-mentioned shortcomings, this application provides an extruder, conductive foam and its preparation method, in order to partially or completely improve the poor stability and preparation problems of conductive foam in related technologies.

[0005] This application is implemented as follows:

[0006] In a first aspect, an example of this application provides an extruder, including an extruder body and a conveying assembly. The extruder body internally comprises a first feed channel, a second feed channel, and an extrusion port. The discharge ends of the first feed channel and the second feed channel converge at the extrusion port, such that the sheet material conveyed by the first feed channel and the rubber compound conveyed by the second feed channel adhere to each other at the feed point of the extrusion port and enter the extrusion port. The conveying assembly includes a pusher and a pusher screw. The pusher is disposed within the first feed channel for conveying the sheet material within the first feed channel to the extrusion port. The pusher screw is disposed within the second feed channel for pushing the rubber compound within the second feed channel to the extrusion port.

[0007] In the above-mentioned process, the extruder is provided with a first feed channel and a second feed channel that converge at the extrusion port. A pusher is provided in the first feed channel and a pusher screw is provided in the second feed channel. The pusher can be used to transport sheet material from the first feed channel to the extrusion port, while the pusher screw can be used to transport gel material from the second feed channel to the extrusion port. This allows the sheet material and gel material to come into contact at the extrusion port and be extruded together to obtain a double-layer extruded material in which the sheet material and gel material are bonded together.

[0008] Using the extruder provided in this application to prepare conductive foam, metal sheets and conductive rubber materials can be co-extruded to bond the mixture of metal sheets and conductive silicone raw materials together. After subsequent vulcanization treatment, the mixture forms an elastic conductive silicone that self-adheres to the surface of the metal sheet, thus obtaining conductive foam. This simplifies the preparation process of conductive foam and improves its stability.

[0009] In conjunction with the first aspect, in an optional embodiment of this application, the first feeding channel is flat, and the second feeding channel is located on one side of the narrower direction of the first feeding channel, so that the adhesive is directly transferred to the surface of the sheet material.

[0010] In conjunction with the first aspect, in an optional embodiment of this application, the second feeding channel is located above the first feeding channel, and the bottom wall of the second feeding channel and the top wall of the first feeding channel share the same wall at the extrusion port.

[0011] In the above implementation process, the first feeding channel is set to a flat shape to facilitate the conveying of sheet material to the extrusion port. The second feeding channel is set above the first feeding channel, and the bottom wall of the second feeding channel and the top wall of the first feeding channel are shared at the extrusion port. The adhesive material conveyed by the second feeding channel can be located on the upper surface of the sheet material at the feeding point of the extrusion port, and then extruded through the extrusion port to obtain a double-layer extruded material with the adhesive material adhering to the sheet material.

[0012] In conjunction with the first aspect, in an optional embodiment of this application, the pusher includes a plurality of rollers, which are rotatably disposed within the first feed channel at intervals along the extension direction of the first feed channel, and the axial direction of the rollers extends along the wider direction of the flat first feed channel.

[0013] In the above implementation process, multiple rotatable rollers are arranged at intervals in the first feeding channel. The axis of the rollers extends along the wider direction of the flat first feeding channel. The sheet material can be placed on the rollers, and through the rotation of the rollers, the sheet material is continuously conveyed to the extrusion port along the extension direction of the first feeding channel for extrusion.

[0014] In conjunction with the first aspect, in an optional embodiment of this application, the conveying assembly further includes two guide members disposed at both ends of the wider direction of the first feed channel to guide the sheet material conveyed by the roller in both sides of the width direction.

[0015] In the above implementation process, guide members are respectively provided at both ends of the wider direction of the first feeding channel, which can guide the two sides of the sheet material in the width direction of the roller conveyor, so that the sheet material is more stable in the extrusion process and improves the extrusion quality.

[0016] In a second aspect, an example of this application provides a method for preparing conductive foam, comprising:

[0017] Using the extruder provided in the first aspect, a metal sheet is conveyed to a first feed channel, and a mixture of conductive silicone raw materials is conveyed to a second feed channel; using a conveying assembly, the metal sheet in the first feed channel and the mixture in the second feed channel are simultaneously conveyed to the extrusion port, and the mixture is extruded through the extrusion port to bond it to the metal sheet, thereby obtaining a double-layer extruded material; the double-layer extruded material is vulcanized to obtain conductive foam.

[0018] In the above-described process, using the extruder provided in the first aspect, the mixture of conductive silicone raw materials is conveyed from the second feed channel to the extrusion port, while a pusher is used to convey a metal sheet from the first feed channel to the extrusion port, so that the mixture and the metal sheet are extruded simultaneously through the extrusion port, obtaining a double-layer extruded material in which the mixture self-adheres to the surface of the metal sheet. Then, the double-layer extruded material is vulcanized to form an elastic conductive silicone compound that self-adheres to the surface of the metal sheet, thus obtaining conductive foam.

[0019] The conductive foam prepared by the method provided in this application eliminates the need for a process of adhering a conductive metal layer to encapsulate silicone. Under long-term pressure, stress repeatedly concentrates on the bottom metal sheet, minimizing damage to the silicone. This improves upon the problem of traditional SMT conductive foam easily detaching from the PCB board or breaking due to stress concentration during use, thus enhancing its overall performance.

[0020] In conjunction with the second aspect, in an optional embodiment of this application, the raw materials for conductive silicone include: 100-120 parts by weight of vinylsiloxane adhesive, 50-70 parts by weight of conductive filler, and 2-5 parts by weight of vulcanizing agent.

[0021] In the above process, 100-120 parts by weight of vinyl siloxane rubber, 50-7 parts by weight of conductive filler and 2-5 parts by weight of vulcanizing agent are mixed together. At room temperature, the mixture can form a uniform and continuous silicone flow so that a continuous and uniform double-layer extruded material can be obtained after extrusion.

[0022] In conjunction with the second aspect, in optional embodiments of this application, the conductive filler is selected from one or more of glass silver-plated conductive powder, nickel powder, or conductive fibers.

[0023] The metal sheet is made of one of copper and its alloys or iron and its alloys.

[0024] Optionally, the metal sheet can be made of stainless steel or phosphor bronze.

[0025] Optionally, the thickness of the metal sheet is 0.05-0.15mm.

[0026] In conjunction with the second aspect, in an optional embodiment of this application, a metal plating layer is provided on the side of the metal sheet facing away from the mixture.

[0027] Optionally, the metal plating material is selected from one or more of gold, tin, or nickel.

[0028] In the above process, stainless steel or phosphor bronze sheets with a thickness of 0.05-0.15 mm have high strength. A metal layer can be formed on the outer surface of the metal sheet by gold plating, tin plating, or nickel plating, which easily bonds with solder paste and solder.

[0029] In a second aspect, this application provides an example of a conductive foam prepared according to the preparation method provided in the first aspect.

[0030] In the above-described process, the conductive foam prepared according to the method provided in this application does not require a process of adhering a conductive metal layer to encapsulate the silicone. Under long-term pressure, the conductive foam provided in this application exhibits stress that repeatedly concentrates on the metal sheet at the bottom, minimizing damage to the silicone. This improves upon the problems of metal plating breakage and easy detachment from the PCB board caused by stress concentration in traditional SMT conductive foams, thereby enhancing its overall performance. Attached Figure Description

[0031] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below.

[0032] Figure 1 A cross-sectional schematic diagram of the extruder provided as an example in this application.

[0033] Icons: 1-Extruder; 10-Extruder body; 11-First feed channel; 12-Second feed channel; 13-Extrusion port; 20-Conveying assembly; 21-Propeller; 22-Push screw; 23-Guide; 100-Conductive foam; 101-Metal sheet; 102-Mixed material. Detailed Implementation

[0034] The embodiments of this application will be described in detail below with reference to examples. However, those skilled in the art will understand that the following examples are for illustrative purposes only and should not be considered as limiting the scope of this application. Unless otherwise specified in the examples, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments whose manufacturers are not specified are all commercially available conventional products.

[0035] Currently, the manufacturing process of SMT conductive foam products typically includes steps such as extrusion, vulcanization, cooling of the elastomer, and bonding of the elastomer and conductive layer through a mold.

[0036] There are some inherent problems in the production process, such as: during the bonding and wrapping of the elastomer and the conductive layer, the adhesive may overflow onto the surface of the conductive layer, reducing the electrical performance of the conductive layer; when the finished product is wrapped or cut, the surface of the conductive layer may appear uneven; and the conductive layer is prone to breakage during molding.

[0037] Furthermore, in actual use, current SMT conductive foam, after being soldered to the PCB, is prone to being lifted by external forces under long-term, repeated compressive loads, thus separating from the PCB and losing its conductivity. In addition, under repeated, concentrated pressure, the metal layer on the surface of the SMT conductive foam may crack, thereby affecting its performance.

[0038] Therefore, this application provides an extruder 1 for preparing conductive foam 100, conductive foam 100, and a method for preparing the same, to simplify the preparation process of conductive foam 100 and improve the stability of conductive foam 100. To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings.

[0039] Please see Figure 1 This application provides an extruder 1, including an extruder body 10 and a conveying assembly 20.

[0040] Please continue reading for more details. Figure 1 The extruder body 10 is provided with a first feed channel 11, a second feed channel 12 and an extrusion port 13. The discharge end of the first feed channel 11 and the discharge end of the second feed channel 12 meet at the extrusion port 13, so that the sheet material conveyed by the first feed channel 11 and the rubber material conveyed by the second feed channel 12 adhere to each other at the feed point of the extrusion port 13 and enter the extrusion port 13.

[0041] Please continue reading for more details. Figure 1The conveying assembly 20 includes a pusher 21 and a pusher screw 22. The pusher 21 is disposed in the first feed channel 11 and is used to convey the sheet material in the first feed channel 11 to the extrusion port 13; the pusher screw 22 is disposed in the second feed channel 12 and is used to push the rubber material in the second feed channel 12 to the extrusion port 13.

[0042] In the extruder 1 provided in this application example, the first feed channel 11 and the second feed channel 12 in the extruder body 10 converge at the position of the extrusion port 13, so that the rubber material output through the first feed channel 11 and the sheet material through the second feed channel 12 are bonded together at the feed point of the extrusion port 13, and then the double-layer extruded material with the sheet material and the rubber material bonded together is obtained by extrusion through the extrusion port 13.

[0043] This application does not limit the shape of the first feeding channel 11. In one possible embodiment, the first feeding channel 11 can be set to a flat shape in order to facilitate the conveying of sheet materials.

[0044] Furthermore, in order to facilitate the contact between the adhesive material output from the second feed channel 12 and the sheet material conveyed in the first feed channel 11 at the feed point of the extrusion port 13, and then extrude them together through the extrusion port 13 to obtain a double-layer extruded material in which the adhesive material adheres to the sheet material, in one possible embodiment, the second feed channel 12 is located on the narrower side of the first feed channel 11.

[0045] It is understandable that the narrower direction refers to the thickness direction of the flat first feed channel 11.

[0046] Furthermore, the second feeding channel 12 is located above the first feeding channel 11, and the bottom wall of the second feeding channel 12 and the top wall of the first feeding channel 11 share the same wall at the extrusion port 13, so that the rubber material output from the second feeding channel 12 is directly located on the upper surface of the sheet-like object output from the first feeding channel 11.

[0047] Furthermore, the extrusion port 13 has a bottom surface, and the sheet material output from the first feed channel 11 exits the extrusion port 13 from the bottom surface of the extrusion port 13.

[0048] For example, the bottom surface of the extrusion port 13 is flat, for sheet material to pass through.

[0049] Furthermore, the top wall of the second feed channel 12 and the top wall of the extrusion port 13 meet at the feed end of the extrusion port 13.

[0050] For example, an extruder body 10 has a cavity formed inside, and a wedge block is provided inside the cavity to divide the cavity into a first feed channel 11 and a second feed channel 12. A second cavity is provided at the tip of the wedge block of the extruder body 10, and the second cavity forms an extrusion port 13.

[0051] The conveying assembly 20 is used to convey materials. The conveying assembly 20 includes a pusher 21 disposed in the first feed channel 11 and a pusher screw 22 disposed in the second feed channel 12.

[0052] The pusher screw 22 is installed in the second feed channel 12. When the pusher screw 22 rotates, it pushes the rubber material in the second feed channel 12 into the extrusion port 13.

[0053] The pusher 21 is disposed in the first feed channel 11 and is used to push the sheet material in the first feed channel 11 to the extrusion port 13.

[0054] In one possible embodiment, the pusher 21 includes a plurality of rollers. The plurality of rollers are rotatably disposed within the first feed channel 11 at intervals along the extending direction of the first feed channel 11, and the axial direction of the rollers extends along the wider direction of the flat first feed channel 11.

[0055] It is understandable that the wider direction refers to the width direction of the flat first feed channel 11.

[0056] When using a roller to convey sheet material, the sheet material is placed above the roller, and the roller rotates under the action of the drive component, thereby conveying the sheet material along the extension direction of the first feed channel 11 to the extrusion port 13.

[0057] Alternatively, in another possible embodiment, the pusher 21 can be configured as a slider that slides within the first feed channel 11 along the extension direction of the first feed channel 11, thereby conveying sheet material placed on the slider.

[0058] Furthermore, in order to improve the smoothness of the movement of the sheet material, in one possible embodiment, the conveying assembly 20 further includes two guide members 23, which are disposed at both ends of the wider direction of the first feed channel 11 to guide the sheet material conveyed by the roller in the wider direction on both sides.

[0059] Furthermore, the extruder 1 also includes a mixing mill, which can transport the raw materials of the rubber compound to the mixing mill, use the mixing mill to stir and mix the raw materials, and then transport the mixed rubber compound to the second feed channel 12.

[0060] Furthermore, this application also provides a method for preparing a conductive foam 100, comprising:

[0061] S1. Using the extruder 1 of this application example, the metal sheet 101 is conveyed to the first feed channel 11, and the mixture 102 of conductive silicone raw material is conveyed to the second feed channel 12. Using the conveying assembly 20, the metal sheet 101 in the first feed channel 11 and the mixture 102 in the second feed channel 12 are simultaneously conveyed to the extrusion port 13. The mixture 102 is extruded through the extrusion port 13 to adhere to the metal sheet 101, thereby obtaining a double-layer extruded material.

[0062] Using the extruder 1 provided in this application example, the metal sheet 101 is conveyed from the first feed channel 11 to the feed port of the extrusion port 13 by the pusher 21, and at the same time, the conductive silicone raw material mixture 102 is conveyed from the second feed channel 12 to the feed port of the extrusion port 13 by the pusher screw 22, so that the metal sheet 101 and the conductive silicone raw material mixture 102 are extruded together from the extrusion port 13, so that the metal sheet 101 and the conductive silicone raw material mixture 102 can be fully bonded together to obtain a double-layer extruded material.

[0063] Compared to using an adhesive to bond a metal film to the surface of conductive silicone, this application uses an extruder 1 to simultaneously extrude a mixture 102 of metal sheet 101 and conductive silicone raw material. This allows the metal sheet 101 and the mixture 102 of conductive silicone raw material to adhere fully, so that the conductive silicone is bonded to the metal sheet 101, resulting in a structurally stable conductive foam 100. There is no situation where an adhesive covers the surface of the metal film and affects conductivity.

[0064] In one possible embodiment, the conductive silicone raw material comprises: 100-120 parts by weight of vinylsiloxane, 50-70 parts by weight of conductive filler, and 2-5 parts by weight of vulcanizing agent.

[0065] For example, the weight parts of vinylsiloxane in the conductive silicone raw material can be one of 100 parts, 101 parts, 102 parts, 103 parts, 104 parts, 105 parts, 106 parts, 107 parts, 108 parts, 109 parts, 110 parts, 111 parts, 112 parts, 113 parts, 114 parts, 115 parts, 116 parts, 117 parts, 118 parts, 119 parts, or 120 parts, or any combination thereof.

[0066] For example, the weight percentage of conductive filler in the conductive silicone raw material can be one or any two of the following: 50 parts, 51 parts, 52 parts, 53 parts, 54 parts, 55 parts, 56 parts, 57 parts, 58 parts, 59 parts, 60 parts, 61 parts, 62 parts, 63 parts, 64 parts, 65 parts, 66 parts, 67 parts, 68 parts, 69 parts, or 70 parts.

[0067] For example, the weight parts of the curing agent in the conductive silicone raw material can be one of 2 parts, 2.5 parts, 3 parts, 3.5 parts, 4 parts, 4.5 parts or 5 parts or any combination thereof.

[0068] In one possible embodiment, the conductive filler may be selected from one or more of glass-plated silver conductive powder, nickel powder, or conductive fibers.

[0069] For example, the conductive filler may be selected from glass silver-plated conductive powder, nickel powder and conductive fibers.

[0070] In one possible embodiment, the metal sheet 101 may be made of copper and its alloys or iron and its alloys.

[0071] For example, the material of the metal sheet 101 can be selected from stainless steel.

[0072] For example, the material of metal sheet 101 can be selected from phosphor bronze.

[0073] For example, the metal sheet 101 may be made of copper.

[0074] Furthermore, the thickness of the metal sheet 101 is 0.05-0.15 mm.

[0075] For example, the thickness of the metal sheet 101 can be one or more of 0.05 mm, 0.06 mm, 0.07 mm, 0.08 mm, 0.09 mm, 0.1 mm, 0.11 mm, 0.12 mm, 0.13 mm, 0.14 mm or 0.15 mm, or any combination thereof.

[0076] Furthermore, a metal coating is provided on the side of the metal sheet 101 facing away from the mixture 102.

[0077] In one possible embodiment, the material of the metal plating layer may be selected from one or more of gold, tin, or nickel.

[0078] For example, the material of the metal plating can be selected from gold.

[0079] For example, the material of the metal plating can be selected from tin.

[0080] For example, the material of the metal plating can be selected from nickel.

[0081] Furthermore, in the double-layer extrusion, the height of the mixture 102 can be 1-5mm.

[0082] For example, the height of the mixture 102 in the bilayer extrusion can be one of 1 mm, 2 mm, 3 mm, 4 mm or 5 mm or any combination thereof.

[0083] Furthermore, during extrusion, the pushing speed of the pusher screw 22 and the pusher 21 can be controlled so that the mixture 102 and the metal sheet 101 are synchronously conveyed to the extrusion port 13.

[0084] S2. Vulcanize the double-layer extruded material to obtain conductive foam 100.

[0085] Vulcanizing the double-layer extruded material can vulcanize the mixture 102 to form elastic conductive silicone that self-adheres to the metal sheet 101, forming conductive foam 100.

[0086] In one possible embodiment, the double-layer extruded material can be vulcanized in a high-temperature tunnel furnace. The temperature of the tunnel furnace can be set to 180°C. During the heating process, the mixture 102 vulcanizes to form an elastic conductive silicone that self-adheres to the metal sheet 101.

[0087] Furthermore, this application example provides a conductive foam 100, which includes a metal sheet 101 and conductive silicone that is self-adhesive to the surface of the metal sheet 101.

[0088] Furthermore, a metal plating layer is provided on the side of the metal sheet 101 that is away from the conductive silicone.

[0089] The conductive foam 100 provided in this application has good structural stability.

[0090] The conductive foam 100 of this application will be further described in detail below with reference to the embodiments.

[0091] Example 1

[0092] Example 1 provides a conductive foam 100, the preparation method of which is as follows:

[0093] (1) Preparation of mixture 102: 100 parts by weight of vinylsiloxane, 60 parts by weight of conductive filler and 3 parts by weight of vulcanizing agent are stirred and mixed at room temperature.

[0094] (2) Using the extruder 1 of this application example, the metal sheet 101 is conveyed to the first feed channel 11, and the mixture 102 of conductive silicone raw material is conveyed to the second feed channel 12; using the conveying assembly 20, the metal sheet 101 in the first feed channel 11 and the mixture 102 in the second feed channel 12 are simultaneously conveyed to the extrusion port 13, and the mixture 102 is extruded through the extrusion port 13 to adhere to the metal sheet 101, thereby obtaining a double-layer extruded material. The metal sheet 101 is a copper sheet with a thickness of 0.05 mm.

[0095] (3) The double-layer extruded material is heated to 180°C for vulcanization to obtain conductive foam 100.

[0096] Example 2

[0097] Example 2 provides a conductive foam 100, which differs from Example 1 in that the metal sheet 101 is a 0.1mm thick copper sheet.

[0098] Example 3

[0099] Example 3 provides a conductive foam 100, which differs from Example 1 in that the metal sheet 101 is a 0.15mm thick copper sheet.

[0100] Example 4

[0101] Example 4 provides a conductive foam 100, which differs from Example 1 in that the metal sheet 101 is a 0.05mm thick copper sheet, and the back of the copper sheet is plated with nickel.

[0102] Example 5

[0103] Example 5 provides a conductive foam 100, which differs from Example 1 in that the metal sheet 101 is a 0.1mm thick copper sheet, and the back of the copper sheet is plated with nickel.

[0104] Example 6

[0105] Example 6 provides a conductive foam 100, which differs from Example 1 in that the metal sheet 101 is a 0.15mm copper sheet, and the back of the copper sheet is plated with nickel.

[0106] Test case

[0107] Using the SMFA series SMT conductive foam produced by Shenzhen Hongfucheng New Materials Co., Ltd. as a control group, conductive foam 100 from Examples 1-6 and the control group was cut into test samples of 3mm x 3mm x 1.5mm. The test samples were then subjected to tests for plating cracking and weld strength.

[0108] The test method for coating cracking includes observing the cracking phenomenon of the metal layer after the sample is compressed 100,000 times at 50% compression. The test results are shown in Table 1.

[0109] The welding strength test was used to measure the welding strength of the sample after it was welded to the PCB board. The test results are shown in Table 2.

[0110] Table 1. Metal Layer Cracking Test Table

[0111]

[0112]

[0113] Results analysis:

[0114] As can be seen from Table 1, compared with the existing SMT conductive foam, the conductive foam 100 prepared according to the extruder 1 and preparation method provided in this application has a lower probability of cracking and falling off, a higher yield, and a more stable structure.

[0115] Table 2 Welding Strength Test Table

[0116]

[0117] Results analysis:

[0118] As can be seen from Table 2, compared with the existing SMT conductive foam, the conductive foam 100 prepared according to the extruder 1 and preparation method provided in this application has higher welding strength after being soldered to the PCB board.

[0119] In summary, this application simultaneously extrudes a mixture of metal sheet 101 and conductive silicone raw material 102 through extrusion port 13, and then vulcanizes the double-layer extruded material to obtain an elastic conductive silicone self-adhesive conductive foam 100 on the surface of metal sheet 101, and the prepared conductive foam 100 has good structural stability.

[0120] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. An extruder, characterized in that, include: Extruder body: The extruder body is provided with a first feed channel, a second feed channel and an extrusion port. The discharge end of the first feed channel and the discharge end of the second feed channel meet at the extrusion port, so that the sheet material conveyed by the first feed channel and the rubber material conveyed by the second feed channel adhere to each other and enter the extrusion port at the feed point of the extrusion port. Conveying assembly: The conveying assembly includes a pusher and a pusher screw. The pusher is disposed in the first feeding channel and is used to convey the sheet material in the first feeding channel to the extrusion port. The pusher screw is disposed in the second feeding channel and is used to push the rubber material in the second feeding channel to the extrusion port. The first feeding channel is flat, and the second feeding channel is located on one side of the narrower direction of the first feeding channel, so that the rubber material is directly transferred to the surface of the sheet material. The second feeding channel is located above the first feeding channel, and the bottom wall of the second feeding channel and the top wall of the first feeding channel are shared at the extrusion port.

2. The extruder according to claim 1, characterized in that, The propulsion component includes multiple rollers, which are rotatably disposed within the first feed channel at intervals along the extension direction of the first feed channel, and the axial direction of the rollers extends along the wider direction of the flat first feed channel.

3. The extruder according to claim 2, characterized in that, The conveying assembly further includes two guide members, which are disposed at both ends of the wider direction of the first feeding channel to guide the sheet material conveyed by the roller in the width direction on both sides.

4. A method for preparing conductive foam, characterized in that, include: Using the extruder according to any one of claims 1-3, a metal sheet is conveyed to the first feed channel, and a mixture of conductive silicone raw materials is conveyed to the second feed channel; using the conveying assembly, the metal sheet in the first feed channel and the mixture in the second feed channel are simultaneously conveyed to the extrusion port, and the mixture is extruded through the extrusion port to adhere to the metal sheet, thereby obtaining a double-layer extruded material; The double-layer extruded material is vulcanized to obtain the conductive foam.

5. The method for preparing conductive foam according to claim 4, characterized in that, The conductive silicone raw material comprises: 100-120 parts by weight of vinyl siloxane adhesive, 50-70 parts by weight of conductive filler, and 2-5 parts by weight of vulcanizing agent.

6. The method for preparing conductive foam according to claim 5, characterized in that, The conductive filler is selected from one or more of glass silver-plated conductive powder, nickel powder, or conductive fiber. The metal sheet is made of one of copper and its alloys and iron and its alloys.

7. The method for preparing conductive foam according to claim 6, characterized in that, The metal sheet is made of stainless steel or phosphor bronze.

8. The method for preparing conductive foam according to claim 6, characterized in that, The thickness of the metal sheet is 0.05-0.15 mm.

9. The method for preparing conductive foam according to claim 4, characterized in that, The side of the metal sheet facing away from the mixture is provided with a metal plating layer.

10. The method for preparing conductive foam according to claim 9, characterized in that, The material of the metal plating is selected from one or more of gold, tin, or nickel.

11. A conductive foam, characterized in that, Prepared by the method according to any one of claims 4-10.

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